COOKBOOK CRITIC
Koji Alchemy: Rediscovering the Magic of Mold-based Fermentation
“Unlike the tang of vinegary pickles, kojizuke is much more subtle. The pickling slurry, which is a simple mix of koji, cooked grain and water, helps elevate the natural flavour of the vegetables through the development of umami.
Besides being a foundation for fermentation techniques of the East, koji has gotten a new spark of life thanks to global interest from curious toques. Koji Alchemy, Rich Shih and Jeremy Umansky’s latest tome, presents a rich encyclopaedia of the mould’s As to Zs. AT A GLANCE
It’s pretty tough to dispute the importance fermentation holds in the culinary world; a core building block of food history of cultures around the world, the technique has produced countless delectable inventions through millennia, including alcohol, bread, yoghurt and more. Fermentation’s importance in the modern culinary landscape is well documented as well, with celebrated chefs weighing in on its versatility, including René Redzepi’s The Noma Guide to Fermentation and Sandor Katz’s The Art of Fermentation.
It’s fitting then, that Katz opens up Koji Alchemy, waxing lyrical in his foreword about his adventures with fermentation. It’s an essential primer for the 318 pages that follow, filled to the brim with diagrams, techniques and uses of the versatile mould. It even provides a detailed history of its discovery and uses throughout the ages, as well as the scientific processes that occur during koji fermentation. In other words, it’s an instruction manual for those looking to start their very own koji projects.
ROAD TEST
Naturally, koji usually conjures up images of Japanese food; after all, the ‘trinity’ of Japanese cuisine (miso, soy sauce and sake), are all products of koji fermentation. With the modern era however, its use has expanded tremendously. But of course, it all starts with one simple step: the cultivation of aspergillus oryzae.
Doing so is not necessarily difficult; it’s not dissimilar to brewing kombucha or feeding a sourdough starter, it just demands a little TLC. Koji Alchemy provides much of the information needed, from rice preparation to storage of freshly made koji. Do note, however, that there exists specific strains of the mould for different preparation techniques. In my sourcing I’ve since found three types available here; miso, tamari (soy sauce), and amazake, which is one of the main ingredients in sake.
Fresh koji may take several days to cultivate, but thankfully dry koji can be found from specialty retailers in Singapore. With a bit of hydration, they can be used as a replacement. Creating miso on the other hand, can take a much longer time. Dark miso, for example, takes a minimum of six months to fully mature. Thankfully, with a bit of help from friends working in local restaurants that were using koji, I managed to get my hands on some light and dark miso, as well as a batch of shio-koji, a Japanese marinade and cure that’s widely used in modern applications.
I decided to start with something a little simpler for starters. Kojizuke was a good base point; as a generic koji vegetable pickle, it offered a wide range of potential candidates, including daikon, carrots and beets. Unlike the tang of vinegary pickles, kojizuke is much more subtle. The pickling slurry, which is a simple mix of koji, cooked grain and water, helps elevate the natural flavour of the vegetables through the development of umami. Harder root vegetables are ideal for this process, developing a characteristic crunch. Softer vegetables can work as well, albeit as sweeter pickles that take only several hours to make. Overall, a simple technique that yields healthy titbits.